Wall v. County of Monroe is a United States Supreme Court case that was decided in 1881. The case involved a dispute between the plaintiff, Wall, and the defendant, Monroe County, over the ownership of a piece of land. Wall claimed that he had purchased the land from the county in 1867, but the county argued that the sale was invalid because it had not been approved by the county board of supervisors. The Supreme Court held that the sale was valid and that Wall was the rightful owner of the land. The Court reasoned that the county had accepted the payment for the land and had not objected to the sale until after Wall had taken possession of the land. The Court also noted that the county had not taken any steps to reclaim the land or to challenge the sale until after Wall had taken possession. The Court concluded that the county had accepted the sale and that Wall was the rightful owner of the land. The Court also held that the county was liable for damages for failing to challenge the sale in a timely manner. This case established the principle that a county must act promptly to challenge a sale or it will be held to have accepted the sale.

Justice Field delivered the dissenting opinion in Wall v. County of Monroe, arguing that the majority had misapplied a previous Supreme Court decision and failed to recognize an important distinction between public and private property rights. He argued that while it was true that governments could not take private property for public use without just compensation, this did not mean they were required to pay for any improvements made by individuals on their own land. In this case, he noted that the county had never taken possession or control of Wall's land; instead, it simply allowed him access to its roads so he could reach his own property more easily. As such, Justice Field concluded there was no legal basis for requiring the county to compensate Wall for his improvements since they were entirely voluntary on his part and provided no benefit whatsoever to anyone else besides himself.